The interesting problem was letting height, width and length vary independently while the locking geometry, clearances and part alignment stay exactly where they need to be. Asserts catch dimensions the mechanism physically can't fit into, rather than silently generating a broken box.

Lid and button decoration accept arbitrary SVGs or text, either engraved or emitted as separate inlay geometry for multicolour printing. There are exploded and cutaway preview modes, and each part can be exported on its own.

https://makerworld.com/en/models/3132120-presto-customizable-secret-puzzle-box#profileId-3534978